Cast iron members excellent in lubricating action of graphite present in abase have been widely used as members required to have abrasion resistance, such as a cylinder liner for an internal combustion engine, a brake drum, and an elevator component (Patent Literatures 1 and 2, etc.). As the cast iron members, members having various compositions, structures, and physical properties have been proposed. As members made of flake graphite cast iron, there are given, for example, members exemplified in Patent Literatures 1 and 2.
In Patent Literature 1, there is proposed an elevator component made of flake graphite cast iron which has a tensile strength of 250 MPa or more and a base hardness of 250 HV or more and which includes a composition containing, in terms of mass %, 2.70% to 3.90% of C, 1.20% to 2.80% of Si, 1.00% to 3.20% of Mn, and the balance of Fe and inevitable impurities, and a structure having a carbide dispersed in an amount of 6.0% or less in terms of an area ratio. Therefore, an elevator component that is excellent in mechanical strength and machinability and can be manufactured easily at low cost can be provided.
Further, in Patent Literature 2, there is proposed a cylinder liner for a ship engine made of flake graphite cast iron which has a thickness of from 30 mm to 350 mm and a tensile strength of 250 MPa or more and which includes a composition containing, in terms of mass %, 2.4% to 3.6% of C, 0.8% or more and less than 2.8% of Si, 1.1% to 3.0% of Mn, 0.01% to 0.6% of P, 0.001% to 0.2% of B, and the balance of Fe and inevitable impurities, and a structure having a carbide dispersed in an amount of 8% or less in terms of an area ratio. Therefore, an inexpensive cylinder liner for a ship engine having a large thickness and high strength can be provided.